Proportionate mortality study of the United Association of Journeymen and Apprentices of the Plumbing and Pipe Fitting Industry

Our plain-English summary of Proportionate mortality study of the United Association of Journeymen and Apprentices of the Plumbing and Pipe Fitting Industry, by E.J. Lehman, M.J. Hein, C.F. Estill (American Journal of Industrial Medicine, 2008).

The study

• Authors: E.J. Lehman, M.J. Hein, C.F. Estill
• Journal: American Journal of Industrial Medicine
• Published: 2008;51(12):950-63
• Cited by: 7 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Background: This study examined causes of deaths among unionized plumbers, pipefitters and allied trades.

Methods: Deaths of union members from the years 1971, 1979, 1987, and 1995 were selected as a representative sample from a computer file provided by the union. These years provided 15,411 deaths for proportionate mortality ratio (PMR) analysis.

Results: PMRs for lung cancer and asbestosis were significantly elevated compared to U.S. white males. PMRs for chronic disease of the endocardium and cardiomyopathy were also elevated. Elevations were not observed in other a priori causes: laryngeal cancer, lymphatic cancer, and neurological disorders. PMRs for transportation accidents for pipe/steam-fitters were elevated in 1971 and 1979, but not in 1987 or 1995.

Conclusion: Despite the limitations of a PMR analysis, study results indicate mortality related to asbestos exposure is, and will continue to be, an area of concern for members of the union.

Copyright 2008 Wiley-Liss, Inc.

In plain English

This study examined causes of death among union plumbers, pipefitters and allied trades. The authors compared 15,411 deaths of U.S. members in 1971, 1979, 1987 and 1995 with U.S. white male deaths, using proportionate mortality ratios (PMRs), which the authors note do not give a true estimate of risk. Lung cancer was above expected (all trades: PMR 1.29, 95% confidence interval 1.23 to 1.35). Asbestosis was far above expected: PMR 11.07 (7.62 to 15.55) for all trades and 17.55 (11.56 to 25.53) for pipe/steam-fitters. Mesothelioma deaths rose from 13 (0.3% of that year's deaths) in 1979 to 57 (1.4%) in 1995. Chronic disease of the endocardium and cardiomyopathy were also elevated. Laryngeal cancer was not significantly elevated overall but was significantly elevated among members with 30 or more years of estimated employment. Lymphatic cancers and non-malignant respiratory disease were not consistently elevated; Parkinson's disease was lower than expected. Smoking histories were not available. The authors concluded that plumbers and pipe/steam-fitters whose careers included years not covered by the OSHA standard will continue to experience effects of past asbestos exposure.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Proportionate mortality ratio (PMR) study comparing union members' deaths with U.S. white males
• Who was studied: 15,411 deaths of U.S. members of the United Association of Journeymen and Apprentices of the Plumbing and Pipe Fitting Industry (plumbers, pipe/steam-fitters, metal trades, sprinkler fitters and others) who died in 1971, 1979, 1987 and 1995; Canadian members excluded
• Exposure: Work in the plumbing and pipe trades; there were no individual exposure measurements. The authors describe the main asbestos-exposing activities as tear-out or disturbance of asbestos-containing insulation (including spray-on insulation) and handling and cutting cement pipe and sheeting. Fiber types are not specified.
• Main results:
  • Lung cancer PMR was significantly elevated for the entire sample: PMR 1.29, CI 1.23 to 1.35
  • Asbestosis PMR was 11.07 (CI 7.62 to 15.55) for the entire cohort, largely driven by pipe/steam-fitters (PMR 17.55, CI 11.56 to 25.53)
  • Among pipe/steam-fitters, the asbestosis PMR increased across the years: 13.49 in 1979, 16.65 in 1987 and 20.77 in 1995
  • Mesothelioma deaths among all union members: 13 in 1979 (0.3% of that year's deaths), 35 in 1987 (0.9%), 57 in 1995 (1.4%)
  • All cancers combined were elevated for the entire sample: PMR 1.15, CI 1.11 to 1.18
  • Overall, laryngeal cancer was elevated but not statistically significantly: plumbers PMR 1.12, pipe/steam-fitters 1.41, combined 1.28
  • Laryngeal cancer PMR was significantly elevated among members with 30 years or more of estimated employment
  • Non-malignant respiratory disease was not elevated
  • There were no consistent elevations in cancers of the lymphatic and hematopoietic systems
  • Parkinson's disease proportionate mortality was lower than expected
  • Two heart disease sub-categories, chronic disease of the endocardium and cardiomyopathy, were elevated in the combined analysis
  • Transportation accidents were elevated among pipe/steam-fitters overall: PMR 1.20, CI 1.03 to 1.38
• The authors' conclusion: The authors concluded that plumbers and pipe/steam-fitters whose working careers included years not covered by the OSHA asbestos standard will continue to experience adverse health effects of past asbestos exposure for the foreseeable future.
• Limitations the authors state:
  • A PMR does not provide a true estimate of risk
  • No individual smoking histories were available, so the effect of smoking on certain causes of death could not be accurately determined
  • Work histories could not be assembled because employment dates were not recorded
  • Only deaths reported to the union for members eligible for death benefits were included
  • Results may not represent the mortality of all workers with substantial employment in plumbing and pipefitting

Topics

Medical terms in this study, explained in our Lexicon: Pipefitter, Lung Cancer, Laryngeal Cancer, Asbestos Exposure.

Related studies

• Proportionate mortality among unionized construction ironworkers — F.B. Stern, M.H. Sweeney, et al. (1997)
• Assessment of mortality in the construction industry in the United States, 1984-1986 — C. Robinson, F. Stern, et al. (1995)
• Proportionate mortality among construction laborers — F. Stern, P. Schulte, et al. (1995)
• A proportionate mortality study of bricklayers and allied craftworkers — J. Salg, T. Alterman (2005)
• Mortality patterns among electrical workers employed in the U.S. construction industry, 1982-1987 — C.F. Robinson, M. Petersen, et al. (1999)
• Mortality experience among Minnesota taconite mining industry workers — E.M. Allen, B.H. Alexander, et al. (2014)

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